How can I write something on an object?
Here's what you can do with the Curve modifier.
For 2.7#
Add your desired text, Shift + A  &gt; Text, then press Tab  to go into edit mode and type in your new text, press Tab again to exit edit mode. Now move your cursor to the center of the bottle mesh you have.
Press Shift + S  and choose cursor to selected. Now add in a circle (Shift + A) under the Curves. Scale it to match the outside of your bottle. Now click back onto the text and convert it to a mesh Alt + C  choose convert to mesh.
Now go under the modifiers tab and choose the curve modifier, select the circle you just created as the Object. You will then have to rotate your text 90 on the x-axis and change the scale of the circle to -1. You may have to mess around with the scale a bit.
For 2.8+
] Everything above will remain the same, though there is no Alt + C shortcut in Blender 2.8, you will have to either use Fn + F3  to search for it or go under the Object Tab -&gt; Convert.

You can also add a Solidify modifier to your text as well to help it stand out a little.